Liquid-Based High Entropy Electrolyte for Li-ion and Li-metal Batteries

Abstract

Lithium-ion batteries have permeated every aspect of modern production and daily life due to their outstanding performance. However, in the face of continuously rising performance demands and emerging application scenarios, existing commercial lithium-ion batteries can no longer meet current demands. As a novel battery system, lithium metal batteries demonstrate higher energy density compared to traditional lithium-ion batteries, yet still face challenges such as lithium dendrite growth, unstable SEI formation, electrolyte consumption, and high safety risks. Although strategies like electrolyte modification, artificial solid electrolyte interphase (SEI) formation, and current collector modification have improved the performance of Li-ion and Li metal batteries, they still struggle to balance characteristics like energy density, rate capability, cycle life, wide temperature range, and safety. In recent years, the high-entropy concept has been introduced into liquid electrolyte-based lithium-ion and lithium metal batteries, achieving preliminary progress. This mini-review focuses on the application of high-entropy effects in liquid electrolytes for lithium-ion and lithium metal batteries. In this review, we summarize methods for modulating electrolyte mixing entropy and configuration entropy. Furthermore, the structure-property relationships between entropy-driven lithium-ion solvation environments and battery performances such as high rate capability, wide voltage window, and temperature range adaptability are discussed. Through a series of characterization studies and theoretical simulations, the regulatory mechanisms are elucidated. Finally, based on existing researches, this review proposes perspectives for future studies and practical development of liquid high-entropy electrolytes, aiming to accelerate technological iteration in novel lithium-ion batteries and high-energy-density lithium metal batteries.